Mitsubishi Electric FR-E720-600 Instruction Manual page 132

Motor brake and stop operation
(4) Protective functions
If any of the following errors occurs in the brake sequence mode, the inverter results in a fault, trips, and turns off the brake
opening request signal (BOF).
Fault Display
Although more than 2s have elapsed after the start command (forward or reverse rotation) is input, the brake opening
E.MB4
request signal (BOF) does not turn on.
Although more than 2s have elapsed after the brake opening request signal (BOF) turned on, the brake opening
E.MB5
completion signal (BRI) does not turn on.
Though the inverter had turned on the brake opening request signal (BOF), the brake opening completion signal (BRI)
E.MB6
turned off midway.
Although more than 2s have elapsed after the brake opening request signal (BOF) turned off at a stop, the brake opening
E.MB7
completion signal (BRI) does not turn off.
NOTE
A too large setting of Pr. 278 Brake opening frequency activates stall prevention operation and may cause E.MB4.
If the sum of the time between Pr. 13 Starting frequency and
Pr. 278 Brake opening frequency + Pr. 280 Brake opening current
detection time is more than 2s, E.MB4 occurs.
Parameters referred to
Pr. 80 Motor capacity, Pr. 81 Number of motor poles
Pr. 180 to Pr. 184 (input terminal function selection)
Pr. 190 to Pr. 192 (output terminal function selection)
Pr. 800 Control method selection
130
Description
Refer to page 76
Refer to page 131
Refer to page 137
Refer to page 76
Pr. 278
Pr. 13
Brake opening request
(BOF signal)
Less than 2s
Output
frequency
(Hz)
Pr. 280
Time
ON